This invention relates to an apparatus for liquid-phase epitaxial growth.
With conventional apparatus for liquid-phase epitaxial growth, a material is dissolved within the apparatus to form a solution for liquid-phase epitaxial growth. The solution is then caused to contact a substrate to form a liquid-phase epitaxial layer on the substrate.
The apparatus of such type is disclosed in U.S. Pat. No. 3,551,219. In the U.S. Pat. No. 3,551,219 a well for receiving a solution for liquid-phase epitaxial growth is shown as made of carbon only. With apparatus provided with such carbon well, however, it was very difficult to obtain a liquid-phase epitaxial growth layer having a desired profile of impurity concentration, particularly a liquid-phase epitaxial growth layer having a lower impurity concentration. The latter case means that it is impossible to obtain, in a case of a light-emitting diode for example, light-emitting diodes showing a good luminous efficiency.
Light-emitting diodes were manufactured using an apparatus whose well for receiving a solution for liquid-phase epitaxial growth is made of carbon only. The luminous efficiency was found to be of the order of 0.1-0.8%.
Likewise, light-emitting diodes were manufactured using an apparatus whose well for receiving a solution for liquid-phase epitaxial growth is made of fused guartz only. The luminous efficiency was found to be of the order of 0.3-1%.